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1.
2.
Histological analyses of monthly collections of Sceloporus jarrovi ovaries are presented. The ovaries undergo a cycle in which yolk deposition occurs in September-October and is followed by ovulation in late November. One corpus luteum forms from each ruptured follicle and undergoes progressive cytoplasmic depletion until mid-June parturition, after which time rapid degeneration commences. Follicular atresia is common during the spring and absent during the summer and early fall. Granulosa cells play an active role in follicular atresia luteal cell formation, and may also be involved in yolk deposition.  相似文献   

3.
Management of the postpartum period is one of the most important factors of stud farm medicine. In horses, owing to the long gestation period, the time from parturition to repeat conception needs be short to maintain an optimal yearly foaling interval. For this reason the features of postpartum ovarian activity and sexual behavior were studied under farm conditions. During 2 consecutive breeding seasons, 107 mares on 5 commercial horse farms were monitored after parturition by regular teasing, transrectal ultrasonography and blood sampling for progesterone. Foalings took place from January 1 to June 15. Body condition scoring was carried out within 5 d and at 60 to 65 d after parturition. The first ovulation occurred within 20 d after foaling in 84.1% (90/107) of the mares. The mean intervals from foaling to the first and second ovulations were 17.8 +/- 1.6 d (+/- SEM) and 40.9 +/- 2.7 d (+/- SEM), respectively. The mean intervals from parturition to the first and second ovulation (P < 0.001), the interovulatory interval (P < 0.01), the second follicular phase (P < 0.001), and the time until the first overt estrus (P < 0.01) were significantly longer in mares foaling before the vernal equinox. In the beginning of the breeding season the intervals from parturition to the first ovulation (P < 0.01), to the second ovulation (P < 0.01), and to the first overt estrus (P < 0.001) were significantly longer for primiparous mares than for multiparous animals. There was a tendency for an increased interovulatory interval and for a longer second follicular phase in mares with decreased body condition after parturition (P = 0.069, P = 0.089, respectively). Suckling and breed had no effect on postpartum ovarian activity. We concluded that under field conditions the resumption of cyclic ovarian activity and sexual behavior in mares after foaling are strongly affected by the season of parturition and parity. In some cases, body condition change and other factors may also play a role in influencing postpartum reproductive function.  相似文献   

4.
Postpartum ovarian activity, uterine involution, and the relationship with hormonal profiles were studied in non-seasonal Shiba goats, with or without nursing of their kids. After parturition, does were allocated to one of two groups, with either weaning on the day of parturition (n = 3; non-nursing group) or weaning at 7–10 weeks after parturition (n = 4; nursing group). Blood sampling (starting 7 days prior to expected day of parturition) and transrectal ultrasound evaluations (starting 2 days after parturition) were conducted every other day or daily to monitor the follicular dynamics, uterus size, and the levels of plasma progesterone, blood glucose, and insulin concentration until at 3 weeks following the first postpartum ovulation. In the nursing group, blood samples were also collected every 10 min for an 8 h period on the day before weaning, 2 and 6 days after weaning, for the analysis of the pulsatile patterns of LH release. In all animals, the blood glucose concentrations increased transiently on the day before parturition and were significantly (p < 0.05) higher than those on the day of parturition (mean of 144 ± 48.8 mg/dl vs 63 ± 11.2 mg/dl). In the non-nursing group, the first postpartum ovulation was observed 9.3 ± 3.2 days after parturition, while in the nursing group, no ovulation occurred before weaning in any of the goats. Here ovulation was observed 18.8 ± 5.0 days after weaning, which was significantly (p < 0.05) later than in the non-nursing group. After first ovulation, all animals in both groups showed early luteal regression. No significant difference in the time required for the completion of uterine involution was recorded between the non-nursing and nursing groups (18.3 ± 4.2 days vs 19.3 ± 3.6 days, respectively), nor in the plasma LH pulse frequency obtained before (1.3 ± 0.5 pulses/8 h), 2 (1.3 ± 1.0 pulses/8 h) and 6 days (2.0 ± 0.8 pulses/8 h) after parturition, in the nursing group. It can be concluded that no ovulation occurs during nursing postpartum, suggesting that nursing is a determinant of the resumption of ovulation in these non-seasonal goats. Ultrasonic observations of the ovary suggest that uterine involution was not influenced by nursing or suckling.  相似文献   

5.
Pregnant mare serum gonadotropin (PMSG) was administered to an adult female red ruffed lemur (Varecia variegata rubra) as part of a medical evaluation to determine the cause of reproductive failure. Successful fertilization, pregnancy, and parturition occurred following PMSG treatment. This report documents an approach to evaluating reproductive failure in an endangered primate species and illustrates the value of collecting objective data on all individuals in a colony for retrospective and comparative analysis. Data from basic and applied research on a variety of species were synthesized to establish a logical protocol for fertility evaluation of an individual. The use of PMSG to induce estrus, ovulation, or fertilization has not been documented for an endangered primate species.  相似文献   

6.
The effects of day of mating and litter size on gestation length in dogs were studied in 36 beagle bitches (age 2-10 yr). The day that plasma progesterone concentrations exceeded 2 ng/mL was considered the day of ovulation; dogs were randomly assigned to be bred once, 1-5 days after the estimated day of ovulation. The interval from mating to parturition was negatively correlated with the number of days from estimated ovulation to mating (P < 0.01). Gestation length (interval from ovulation to parturition) was almost constant at 63.9 +/- 0.2 days (mean +/- S.E.M.), with no significant relationship between the number of fetuses and the duration of gestation.  相似文献   

7.
Summary

Five structural types of the adult ovary were distinguished in a parthenogenetic viviparous scorpion Liocheles australasiae based on the presence or absence of swollen ovarian diverticula (SD) containing embryos and/or empty ones (ED) as remnants of past pregnancies. These structural types seem to correspond to the following ovarian functional phases: the ovary (1) with SD and without ED corresponds to the first pregnancy; (2) without SD and with ED to after the first parturition; (3) with SD and ED to the second pregnancy; (4) without SD and with old and new ED to after the second parturition; and (5) with SD and old and new ED to the third pregnancy. Such correspondence indicates that a female can repeat pregnancies at least three times. Some possible cases in which the present structural types correspond to other functional phases were also discussed.  相似文献   

8.
This study investigated possible female-related causes for inconsistent success among reproductive pairs in the zoo-based red wolf (Canis rufus) population. Females (n = 13) at seven institutions were assessed for evidence of ovulation and normal reproductive cycles through the measurement of estradiol and progesterone metabolite excretion in feces. Fecal cortisol metabolites (FCM) were also measured. Factors potentially affecting FCM and/or estrous cyclicity were recorded, including exhibit status (on vs. off), reproductive history (proven vs. unproven), copulatory behaviors (ties observed: yes or no), pregnancy/parturition (pups or no pups produced), and translocation before the observed breeding season (yes or no). No differences were observed in baseline FCM between females housed on versus off-exhibit (p = .46) or between females producing pups and those who did not (p = .19). Baseline FCM were significantly lower among females observed in copulatory ties compared to females never observed in a tie (p = .04), and tended to be higher in females translocated before the breeding season compared to females in existing reproductive pairs (p = .11), and among historically unproven females compared to proven females (p = .11). All females evaluated had an endocrine profile indicative of ovulation and among the four females translocated to be paired with a new male before the breeding season, two had successful pregnancies, producing litters. Therefore, despite observed differences in baseline FCM among factors, estrous cyclicity and reproductive success are unaffected by translocation for the formation of new reproductive pairs in the zoo-based red wolf population.  相似文献   

9.
目的:研究溴隐亭不同给药方案在治疗高泌乳素血症(HPRL)女性不育症中的临床疗效,关注其对女性促性腺激素诱导排卵的影响。方法:本研究共纳入60例就诊于我院的确诊为高泌乳素血症不孕不育患者,随机分为两组。分为研究组与对照组:研究组采取先口服溴隐亭调整血清泌乳素水平至正常后予以促性腺激素诱导排卵;对照组采取促性腺激素与溴隐亭同步治疗方案。结果:观察两组患者的促排卵周期数、平均用药天数、雌二醇水平及妊娠率,两组治疗前后的血清泌乳素都显著改善(P0.05);但是两组之间相比,采取溴隐亭药物治疗后诱导排卵的研究组在促排卵、雌二醇水平和妊娠率方面具有显著优势(P0.05)。结论:采用溴隐亭治疗高泌乳素血症患者,调整至正常后再使用促卵泡激素药物促排卵治疗不孕不育具为较优的治疗方案。  相似文献   

10.
The growth of the follicle and oocyte in the Indian gerbil (Tatera indica) was a continuous process. The relationship between follicle and oocyte or its nucleus was log linear, represented by the equation log Y =a +b logX.A linear relationship (Y =a +bX)existed between the oocyte and its nucleus. The number of stages I and II follicles varied significantly during the oestrous cycle. Maximum percentage of stage I follicles was observed during oestrus and metoestrus, while stage II follicles were abundant during dioestrus, metoestrus and pro-oestrus. These follicles were significantly more in number than other types of the follicles. The occurrence of comparatively larger follicles during pro-oestrus and the presence of newly formed corpora lutea at oestrus, indicated ovulation in the early oestrus.  相似文献   

11.
Samples of the shovelnose guitarfish Pseudobatos productus were collected on board a vessel and at landings of artisanal commercial fisheries in the Gulf of California from May 2004 to June 2007. Samples of 650 females, 2047 embryos and 484 uterine eggs were examined. The reproductive cycle is annual, ovulation and parturition occur in July, the uterine eggs are in diapause for 9 months (July–March) before an accelerated growth of embryos of 3 months. Histological analyses of the uterine wall of pregnant females suggested that no secretions were used for embryo nourishment. The standard percentage of water content was 48·6% in fertilized eggs and 80·75% in full‐term embryos. Dry mass loss during embryonic development was 16·3% and the chemical balance of development was 0·84. This indicates that P. productus is a strictly lecithotrophic, viviparous species, that makes no maternal contribution of nutrients during embryonic development.  相似文献   

12.
Endocrine data and characteristics of nonconceptive ovarian cycling and pregnancy are limited within the genus Callithrix to the common marmoset (C. jacchus) and Wied's black tufted‐ear marmoset (C. kuhlii). This article presents patterns of urinary pregnanediol‐3‐glucuronide (PdG) excretion, as determined by enzyme immunoassay, throughout the course of ovarian cycling and pregnancy in white‐faced marmosets (C. geoffroyi). Furthermore, characteristics of reproductive parameters including litter size, duration of gestation, maternal age, and information about ovarian cycling following administration of contraceptives are also described. A steep increase in PdG, an indication of ovulation, characterizes normative ovarian cycles, with peak‐to‐peak intervals between cycles being 27.82 ± 1.49 days in length. PdG excretion (μg/mg Cr) across pregnancy peaked during the 1st and 2nd trimesters (1st = 20.71 ± 2.98, 2nd = 21.16 ± 2.60) and declined gradually to near preconception levels over the 3rd trimester until parturition (3rd = 5.74 ± 1.60). Gestation lasted 148.55 ± 1.89 days. Most pregnancies (82.8%) resulted in an immediate postpartum ovulation (PPO) of 17.45 ± 2.22 days with 58.3% of PPOs resulting in conception. No differences in PdG excretion during the 1st trimester between full pregnancies and miscarriages were found, and pregnancy characteristics such as litter size, duration of gestation, and maternal age were not associated with PdG concentrations. Administration of cloprostenol resulted in shorter peak‐to‐peak cycle durations, but ovulation was detectable with similar concentrations of peak PdG to a normal nonconceptive cycle. Conversely, medroxyprogesterone acetate (DMPA) injections resulted in little to no PdG excretion across the ovarian cycle. Both methods of contraception providing effective prevention of conception. Overall, these results show that strong similarities in reproductive parameters persist within the genus Callithrix and to a lesser extent across the Callitrichidae family. Am. J. Primatol. 74:1044‐1053, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

13.
目的 应用统计过程控制理论分析指导医院服务质量持续改进。方法 联合使用多个控制图方法对医院服务质量评价指标的变化趋势进行监控,及时发现过程中的异常波动,制定针对性措施实施过程改进。结果 找出了影响医院服务质量数据波动的主要原因,制定改进措施,取得了良好的管理效果。结论 控制图可以准确全面反映医院服务质量的总体情况和过程控制情况,根据数据异常分布状态找到潜在的影响服务质量的原因并进行持续改进,是有效的过程管理工具。  相似文献   

14.
Treatment with PGF resulted in the termination of pregnancy in 16- and 19-day pregnant rats, but not in 10- or 13-day pregnant rats. Rats that aborted displayed a rapid onset of maternal behavior when tested with foster pups. Aborted rats also displayed sexual receptivity and ovulation: these phenomena resemble the sequence of events following hysterectomy on the same days of pregnancy. Both can be related to the events surrounding normal parturition in the rat. The results are interpreted as due to a pregnancy-induced deactivation of the factor in the uterus that prevents estrogen from stimulating maternal behavior in nonpregnant females. In the absence of this factor, the PGF-induced rise in estrogen secretion facilitates maternal behavior and sexual behavior and induces ovulation.  相似文献   

15.
Body temperature and serum progesterone concentrations were measured in mares to determine if a change in either could be useful in predicting estrus, ovulation or parturition. There was no significant correlation (P > 0.1) between rectal temperature and the environmental temperature or progesterone concentration. Progesterone concentration did correlate with stage of estrous cycle and the stage of pregnancy. Significant differences (P < 0.05) in temperature were noted at different times throughout the day. No change in temperature occurred that could be utilized to predict estrus, ovulation or parturition. The changes in serum progesterone concentration were only useful in detecting estrus.  相似文献   

16.
Sceloporus aeneus exhibits reproductive bimodality. That is, one taxon (Sceloporus aeneus bicanthalis) is viviparous whereas the other (Sceloporus aeneus aeneus) is oviparous. Morphological differences in luteal and oviductal structure were examined. Oviparous and viviparous females have distinct corpora lutea that form immediately after ovulation and remain active until just prior to oviposition or parturition. Luteal activity is correlated positively with follicular atresia. The oviduct of both subspecies is divided into three distinct morphological regions: an anterior infundibulum, a median uterus, and a posterior vagina. The infundibulum and vagina of females exhibiting either parity type are similar, whereas distinct differences in utering morphology are apparent. Primarily, these differences include the loss of uterine glands and a reduction in epithelial cell height in the viviparous form. Moreover, viviparous females possess a simple but well-developed chorioallantoic placenta and a simple choriovitelline placenta. Chorioallantoic placentation is associated with a significant increase in uterine vascularity, indicating a role in gas and/or water exchange. The evolution of viviparity and placentation are discussed in relation to these observations.  相似文献   

17.
The southern snow skink Niveoscincus microlepidotus is a viviparous alpine lizard with biennial reproduction, in which embryos are fully developed before winter but parturition is delayed until spring. We aimed to determine whether, in this species, in vitro uterine preparations are responsive to arginine vasotocin (AVT) and prostaglandin (PGF) in autumn and spring, and whether pre-treatment with the β-adrenergic agonist isoproterenol decreases the effectiveness of AVT in stimulating uterine contractions. Using the spotted snow skink (Niveoscincus ocellatus), an annually breeding species, we aimed to determine influences of temperature and the β-adrenergic system upon the response to AVT in vivo. In both N. microlepidotus and N. ocellatus females are more responsive to AVT than to PGF, and that the response to AVT is decreased, but not prevented, by β-adrenergic stimulation. In N. microlepidotus, uteri are equally responsive in both seasons to the hormones administered. In N. ocellatus environmental conditions, specifically, temperature, modulate the response to AVT in vivo with the time to parturition increasing as temperature decreases. We conclude that in these viviparous squamates the endocrine cascade leading to parturition is modulated by the β-adrenergic system, and that this may reflect the mechanism by which the timing of parturition is tied to suitable environmental conditions.  相似文献   

18.
Abstract

Plots of oviposition times for an unselected group of 84 female Coturnix using the circular mean time for each bird on a central index time indicated a regularity in the data for individual birds. An analysis of pooled data using a moving average showed agreement with the temporal occurrence of the photoresponsive interval reported in the literature for gonadal development. These data were used to support a modification of existing hypothesis on the control of oviposition and ovulation.  相似文献   

19.
The annual oviductal cycle of the Cottonmouth, Agkistrodon piscivorus, is described using electron microscopy. This is only the second such study on a snake and the first on a viperid species. Specimens were collected in reproductive and nonreproductive condition throughout the year and five ultrastructurally unique regions were recognized: the anterior infundibulum, posterior infundibulum, glandular uterus, nonglandular uterus, and vagina. Except for the anterior infundibulum and vagina, which exhibit no seasonal variation in ultrastructure, the oviduct becomes highly secretory at the start of vitellogenesis. This includes the entire luminal border of the uterus, the tubular glands of the glandular uterus, and the luminal border and sperm storage tubules of the posterior infundibulum. The secretory materials produced in the oviduct vary among regions of the oviduct, and also can vary among time periods in the same region of the oviduct. Variation is especially evident in the sperm storage tubules. Secretory activity in the sperm storage tubules ceases after ovulation, but the tubular glands of the glandular uterus remain secretory until parturition, at which time secretory activity in the varying sections of the oviduct decreases dramatically. After parturition, the oviduct remains in a dormant state until the next reproductive season. The seasonal variation in oviducal morphology mirrors the temperate primitive reproductive cycle known for some pitvipers. Uterine glands of A. piscivorous are more similar in secretory activity to those of an oviparous lizard than a viviparous colubrid snake, suggesting variation in uterine gland morphology between snakes of different families. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

20.
Viviparous lizards living in cold climate of high altitude often exhibit atypical reproductive cycles, in which mating and fertilization occur synchronously and annually with parturition occurring at the end of the year. Nevertheless, detailed case studies on atypical reproductive cycles are few. Using anatomical data combined with behavioral observations, we examined the reproductive cycle of a common Asian agamid, Phrynocephalus vlangalii, from a high‐elevation area in Sichuan, China. Male spermiation of P. vlangalii occurred in May, and spermatogenesis began in June and reached a maximum in October. For females, ovulation and fertilization occurred in May, and females developed gestation and pregnancy in 3 months from June to August, without vitellogenesis during this period. Females gave birth synchronously in late August, then vitellogenesis began and lasted until May of the next year. All adult males and females were synchronized in the same reproductive condition each month. The synchronous and annual reproductive cycle of P. vlangalii clearly represents an atypical cycle. The male courtship and mating behaviors were concordant with gonadal cycle and mainly happened in May and June. Despite the short growth period for neonates, they had a high over‐winter survival rate of 84.4%, suggesting that autumn parturition did not generate high costs to this reproductive cycle. We propose that the high over‐winter survival rate of neonates is likely linked with female delayed sexual maturity, female asynchronous vitellogenesis and gestation, large relative clutch mass (RCM), and adult‐offspring burrow sharing behavior during hibernation.  相似文献   

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